/Engine/Plugins/Online/OnlineSubsystemUtils/Source/OnlineSubsystemUtils/Public/OnlineSubsystemUtils.h
Determine if the subsystem for a given interface has been instanced
true if the subsystem has been instanced
namespace Online { static bool Online::DoesInstanceExist ( const [UWorld](API\Runtime\Engine\Engine\UWorld) * World, const [FName](API\Runtime\Core\UObject\FName) & SubsystemName ) }